eROSITA will therefore provide for the first time a large, homogeneously selected X-ray sample of groups for detailed studies with future generations of X-ray instruments [1]}, [2]}, [3]} detailed in the next sections and for the pointed phase of eROSITA itself, in a similar fashion as ROSAT. In particular, given the large field of view, pointed observations of eROSITA will provide valuable information for the outer regions of groups and their metallicity.
These upcoming data sets are all the more interesting in the context of the expected spectral model improvements driven by microcalorimeter data, which will further ensure that the results derived from lower-spectral resolution CCD observations are robust.
